Method of making metal-clad panels



G. NRQUls-r' ou2 5;1949- 42,485,648 lnruouor mima wm. cum lumens u 'fo'lriginaljrned oct. s, m44- 3- Shoots-Sheet v1 y v 'A TTQ'QNEX L f r V l 25, 1949. l H. NoRQLus-r lmao or#` nimma maui. cum rmusns A Sshhtgfsmn s original FiledOf-L 3, 194,4I l v Y l A By l WO2/viv Patented Oct. 25, 1949 UNITED s'rA'rl-:s PATE-.Nr orsicil-:i r

application mm s, 1944, snm ne.

Divided and this application August 23, 1946, Serial No. 692,528

Claims. (Cl. 28-148) division of my copending applicationV Serial No. 5

557,022, led October 3, 1944.

Metal clad panels, comprising a metal sheet bonded to a base sheet, may be advantageously employed in the manufacture of packing cases,

shelving, table tops, counters, cabinets and numerousother finished products where strength, durability, lightness in weight and attractive appearance are important requisites. The base sheet customarily used comprises a layer. sheet or panel of wood, plywood, berboard, paperboard,

wallboard or other composition material and the surfacing metal customarily used comprises a sheet or layer of stainless or galvanized steel, copper, brass, aluminum, magnesium or other suitable metal. Where the base sheet is relied upon to give substantial added strength to the construction, a plywood base sheet. comprising a plurality of thin layers of wood cemented together 'by a resinous cement, can be advantageously employed.

As a step in manufacture of a finished product from such metal clad panels, it is often necessary to form flanges or side sections which extend-at a predetermined angle to the main or body section of the panel, and to join the adjacent ends of such anges in provide a smooth and finished corner. It has heretofore been customary to cut out or remove a V-Section from the corner of both the base sheet and metal facing sheet prior to forming of the flanges and the shaping thereof at the proper angle to the main section of the panel. Attempts to later solder together the adjacent severed ends of the metal which form the corner ends of the anges, has produced corners lacking rigidity and strength and unsightly in appearance. This weakness and lack of strength is in part due to blow-holes in the solder caused by gases generated when the hot solder flowing between the corner ends of the metal flanges contacts the base sheet and the adu ners on metal clad panels which possess great n strength and rigidity.

Other objects and advantages of this invention will become apparent as the. disclosure proceeds.

Although the characteristic features of this in- 2 claims appended hereto, the invention itself, and the manner in-which it may be carried out. may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part hereof. in' which Fig. 1 is a perspective of the base sheet usedfin forming thevmetal clad panel and which may comprise plywood. nherboard. or other composition material;

Fig. 2. is a perspective view of the metal sheet to beapplied to the base sheet;

Fig. 3 is a perspective view of the base sheet after the corners thereof Ahave been notched;

Fig. 4 is a perspective view of the corner notched base sheet adhesively secured to the metal sheet, leaving the corners of the metal sheet exposed;

Fig. 5 is a perspective view of the metal clad panel showing ange defining grooves cut in the base sheet;V

Fig. '.6 is an enlarged fragmentary cross-sec- ,tional view taken through .the metal clad panel along line S-i of Fig. 5, showing particularly 'the 5 flange Vdefining groove cut in the base sheet;

Fig. 'I is an enlarged fragmentary perspective view of a corner portion of the metal clad panel shown in Fig. 5, this view particularly illustrating details of the corner formation prior to crimping the corner section of the metal sheet;

Fig. `il is a perspective view of the panel as shown in Fig. 5after the corner sections of the metal sheet have been crimped;

Fig. 9..is an enlarged fragmentary perspective view of a corner portion of the panel shown in Fig. 8; 4

Fig. 10 is a perspective view o t the metal cla panel after the anges thereof have been shaped to the desired contour;

Fig. 11 is an enlarged fragmentary perspective view illustrating the corner formation of the flanged panel in greater detail;

Fig. 12 is an enlarged fragmentary cross-sectional view taken through one of the flange sections and the base section of the :Banged panel shown in Fig. 10, as the same appears when viewed along line Il -ll of Fig. 10;

Fis. 13 is an enlarged fragmentary cross-sectionalY view through the corner portion of the flanged panel as the same appears when viewed along the line of Fig. 11, this view particularly showing the corner section of the metal sheet folded to provide a quadruple p ly corner reinforcing rib;

vention will be particularly pointed out. in the Fig. 14 is a perspective view of a metal clad panel comprising a base sheet and attached metal sheet in which the base sheet is provided with flange dening grooves prior to notching out the corners of the base sheet;

Fig. shows the panel illustrated in Fig. 14 at a further stage of manufacture and in which lthe base sheet has four flange dening grooves cut therein and the wedge shaped corner sections removed therefrom, the facing metal remaining uncut and not weakened;

Fig. 16 is an enlarged fragmentary top plan view of the notched panel illustrated in Fig. 15, this view showing the corner formation of the panel in greater detail prior to shaping the flanges thereof;

Fig. 17 is an enlarged edge view of the corner of the panel as it appears when viewed along line l'l-l'l of Fig. 16;

Fig. 18 is a perspective view of the panel having the flanges shaped to extend at an angle of about 45 to the facing section;

Fig. 19 is an enlarged fragmentary perspective view particularly illustrating the corner formation of the hanged panel shown in Fig. 18; and

Fig. 20 is a cross sectional view ofthe flanged panel as it appears when viewed along linek 20-20 of Fig. 18.

Similiar reference characters refer to similar parts throughout the several views of the draw ings and specification.

In accordance with this invention, the metal clad panel is formed from a base sheet w having a metal sheet m firmly and permanently cemented to one side thereof. The base sheet w as shown in Fig. 1 may be advantageously In one method of assembly the corners of the base sheet w are notched or cut out as at 2, shown in Fig. 3, before the base sheet is cemented or secured to the metal sheet m. The V-shaped corner notch is so formed and shaped so that when the flanges of the metal clad panel are formed a smooth and finished comer construe-j, tion is produced. For example, when the finished flanges are to extend at an angle of substantially 90 to the facing section of the panel, the apex, of the corner notch, as shown in Fig. 3, has- 'and 7. Grooves 5 and grooves 6 generally V- shaped in cross-section are cut in the base sheet, as shown inv Fig. 5, the adjacent ends of the grooves 5 and 6 intersecting or meeting at the apex of the corner notch 2 cut in the base sheet. The panel thus formed is defined by a formed from a plurality of superimposed thin layers of wood or veneer, which are firmly bonded by a suitable cement. A base sheet w formed of plywood can be made so as to possess great strength when the wood or veneer layers are cemented together by phenolic and urea compounds and then subjected to heavy pressure and substantial heat. Such plywood sheets and their method of manufacture are well-known in the art. It is understood, however, that the metal surfacing sheet m as shown in Fig. 2 may be applied to a base sheet formed from other fibrous sheet materials, it being appreciated that a base sheet is selected which would best serve the purpose for which the final product is to be used. For example, where a panel is to be formed which possesses high heat or high sound dampening or insulating qualities, a suitable liber board or ber base sheet may be used, but where great strength and rigidity is required, a plywood base sheet is preferably used. Therefore, it is understood that the words base sheet as used herein is intended to broadly refer to laminated plywood, berboard, paperboard, wood, or any other relatively rm sheeting. material adapted for the purpose for which the final product is to be used.

'This invention more particularly relates to the construction and formation of iianges and corl-ners on metal clad blanks providing a panel having flanges or side wall sectionsextending at an angle to the main section of the panel, and to the construction and formation of the corners l of the panel. y

There is shown in Fig. 10 of the drawings a meta-l clad panel wherein the flanges thereof exx tend at an angle of approximately 90 to the i facing section thereof, and Fig. 18 illustrates another type of metal clad panel in which the flange sctions extend at an angle of approximatelyr45 to'tthe facing section thereof.

facing section Il and flange or side wall sections 9 and I0, the ends 3 of the ange Section 9 and the ends 4 of the ange section I0 being beveled so that these adjacent ends are substantially parallel when the flanges have been fully formed.

Wherethe anges of the panel to be formed are to extend at an angle of approximately to thel facing section Il, the corners of the metal sheet m may be beveled oil. as at l. prior to attachment of the metal sheet m to the base sheet w, so that when the anged panel has been completed as shown in Fig. 11, no sharp corners of metal project beyond the adjacent flanged "edges of the base sheet.

In the next operation, as shown in Figs. 8 and 9, the corners of the metal sheet are crimped on a metal die so that the desired rib forming folds will be formed in the corner metal. As shown more particularly in Fig.A 9, the medial crimp line 1 is formed in the corner metal, and a pair of intermediate crimp lines 8 are also formed in the corner metal, dividngthe corner metal into a pair of intermediate triangular segments l and a pair of spaced triangular segments 8', which are later to be folded together in overlap or accordion relationship to provide the quadruple-ply comer-reinforcing rib shown in Fig. 11. Such a quadruple-ply corner reinforcing rib can advantageously be formed where the flange sections of the nished panel are to extend at right angles to the facing section thereof. It will be appreciated, however, that where the flanges are to extend at an angle ofapproximately 45 to the facing section, the oor'- nerrib vmay be formed as a double ply construction requiring only 'the formation of a medial fold line 'I in the corner metal as shown in Fig. 16. It will be further appreciated that the corner metal may be folded to provide a six ply reinforcing rib by the provision of the necessary number of fold lines in the corner metal. It is generally desirable to provide a suicient number of folds in the corner metal so that the reinforcing rib as formed will vnot extend inwardly beyond the plane ofthe inside face of the base sheet of the finished iianges.

Suitable holes or apertures 20 may be punched in the flanged sections 9 and I0 of the panel shown in Fig. 8 at the same time that the corner metal crimping operation is performed. The holes 2l assauts may be punched any convenient desired distance In s .subsequent operation, the flat panel as shown in Fig. 8 is placed in a formingpress and. the flanged sections are bent tothe desired angle withrespect to the facing section Il, as shown in Fig.l0. The press used for this purpose is s finished mitered loin: when the mages -are formed.-

equipped with a shaping mandrel or die, which bends and shapes theV metal parts of'the zlanges.l

Due to the line folds 1 and 8 in the corner metal the corner metal will normally fold into the vform ofa rib, as illustrated in Figs. 11 and y13, and so that the intermediate triangular segments 1'- will tightly overlap one another and the spaced triangular segment 8' will tightly overlap the adjacent faces of the intermediate triangular segments 'Iv'. The spaced triangular ,segments I' will 'also snugly overlap the adjacent beveled ends 4 and 4 of the ilange sections 9 and Il of the base sheet, thus forming a quadruple ply metal -reinforcing rib snugly wedged between the beveled ends 3 and 4 of the flanged sections I and I4 ofthe base sheet. The accordion folding of the triangular segments 'l' and 8' may be positively assured by the provision of knives at the corners of the mandrel to facilitate the folding operation. Such means are usually not needed in the formation of a double ply rib, but vmay be used conveniently in cases where a 4-ply or 6-ply corner reinforcing rib is to be formed. The plies of the reinforcing rib may, if desiredfbe further strengthened by the application of welding or soldering metal to the outer corner as at 2|, or to the inner "corner as at 22 as illustrated more particularly in Fig. 13. The outer corner niay then beburnished or groundto'give the corner a smooth and finished appearance.

There is shown in Figs. 14 to 17 inclusive,

asomewhat modified series of steps which may' be` used in the formation of a flanged metal clad o panel. In the construction here shdwn the metal clad sheet 1n is first attached to the base sheet w. The grooves 5 and 6 are then cut in the base sheet, as shown in Fig. 14,`so. that the flange forming sections 9 and In ofy the base sheet w are substantially severed from the main section Il lof the base Ysheet by the grooves 5 and i. Thegrooves 5 and 8 may be cut by a grooving wheel, and extend to meet at a corner inter- .sectionfpoint '|2. If a grooving wheel is used,L

the ends 5' and 6' of the grooves B and 4 may extend slightly beyond the intersection point I2 to make sure that the fibrous sheet w is fully cut'through at the intersection point l2, thus avoiding the necessity of chiseling out any remaining fibrous material at the intersection point In the next operation, V-shaped segments, as shown in Fig. 15, are cut out from' the base sheet w at the corners thereof, the apex of the triangular cut out being positioned adjacent at the intersection point I2. The triangular shaped segments may,r bereut from the corners of the base sheet by an automatic machine of improved design. The shape of the triangular cut-out should be such that the adjacent anged ends 3 and 4 of the fibrous sheet w, will meet to form a mitered joint when the flanges of the panel'are bent to the desired shape. It will be noted by referring more ,particularly to Figs. 3, 4, 15 and 17 that the flange ends 3'and 4 are cut on a bias to insure metal.

shaped segments l'. l When the corner-notched metal clad panel as illustrated in Fig. 15 is placed in a forming press, the forming die shapes the flange sections 9 and l0 into the desired flanged position and the paired triangular segments 1 ofthe corner metal will naturally fold together into parallel relationship and become tightly wedged between the adjacent ends 3 and 4 of the ilange sections l I and It of the Vbase sheet. Thus it will be noted that the reinforcing rib is formed from the excess corner metalwhen the 'flange sections are bent into position. The metal rib formations greatly strengthens and reinforces the corners of the finished panel. The corners of the flanged panel may be further strengthened by seam welding or soldering the exposed outer corner 2l of the metal or the inner edge 22 of the rib, and

`when the metal corner is then vburnished or ground it` presents a smooth and finished appearance with no corner seam visible.

Improved metal clad flanged panels formed as above described maybe manufactured at relatively low cost and at a. high production rate. Base sheets and metal fsheets composed of selected materials may be assembled and cut to provide a metal clad panel of any desired size and form. The corners of the -basesheetmay beA miter cut so that the corner ends 3 and 4 correspond to the angular-ity at which the finished flanges of the panel are to extend. The V-shaped grooves 5 and 6 are cutso'as to substantially sever the fibrous base sheet w and are located so as to `form flanges 9 and I0 of the desired width. The V-shaped grooves 5 and 4 should have a base width sum/cient to permit formation of flanges of the desired angularity when the nished anged panel is formed. A slow drying bonding cement may be forced into the grooves 5 and t. and also deposited between-the adjacent free ends 3 and 4 of the flange sections t and il of the base sheetfthereby firmly bonding fng'ether the flange sections 9 and Il Vto the main section of the base sheet, and the adjacent flange ends 3 and 4 to the intertwined metal rib.

It will be noted that the metal sheet presents unbroken corner sections tightly wedged between the flange ends 2 and 4. The double ply metal ribsl formed by thev accordion folded triangular segments may be soldered or seam welded together at 2| or 22 to provide a corner construction of great strength and rigidity. After welding or soldering, the exterior metal surface of the corner may be burnished or ground to give the corner a'ilnished appearance. The panel as thus constructed possesses great strength, and the corners possess special strength and resist# ance to strains and blows.

It will be appreciated that the flanges of the panel may be made of any desired width, and may be formed to extend at any desired angle with respect to the main section Il of the panel. It is therefore understood that this invention il ,departing from the brad L l. not limited to panels having flanges of any par-v ticular width, or flanges extending at any particular angle to the main'y section of the panel.

Flanged metal clad panels may be used in the manufacture of nnishedproductsfwhere extra strong corners 'of neat and finished appearance are required. By constructing the hanged metal clad panelsin accordancewith the teachings of this invention, a flanged panel yis providedof unusual strength and rigidity. adapted to meet all requirements, and' which can be manufactured at relatively low cost.

It is understood that the improved metal clad -tails required by the vparticular application, and

that changes and modiilcatlons in the form, construction and arrangement and combination of the several parts may be made and substituted for those herein shown and described without vention. I

What is claimed is: 1. The method of making s iianged metal clad panel formed from a base sheet and av flexible metal sheet which comprises, removing trianguy lar, shaped segments from the corners of the base sheet to deilne the adjacent ends of the ange sections thereof, adhesively securing the base sheet to the metal sheet so as to leave the corner portions of the metal sheet uncovered, and exposed, cutting grooves in the base sheet to further deilne the main section and'flange sections,

' forming a crimp in the corners of said metal sheet, bending the metaLsheet-along said grooves to form corresponding metal anges and folding the metal corners to provide rib formations extending between the adjacent ends of the flange sections of the base sheet.

y2. The method of making'- a flanged metal cladl panel formed from a base sheetcemented to a flexible metal sheet which comprises, cutting grooves in the base sheet to define/a1 main section and a plurality of flange sections, removing triangular shaped segments from the corners of l Y said base sheet'to define the adjacent ends of the flange sections'and' substantially simultaneously forming a crimp in each corner of the metal sheet,

bending the metal sheet along said grooves toy form corresponding metal flanges and substan tially simultaneously foldingthe crimped corner metal to provide rib formations extending betweenfthe adjacent ends of the ange sections of the base sheet.

3. The method of making a angedmetal clad panel formed from a, base sheet and a exible 4metal facingsheet which comprises, removing B6 1,165 86o triangular shaped segments fromthe corners of the base sheet to define the adjacent ends -of the ange sections thereof, adhesively securing the base sheet to the metal sheet so as. to leavethe principles of this in-v y 30 cutting a V-shaped notch in a cornerof the base Number further denne the main muon and sance sa:

tions,. forming a crimp in the' corners of said s metal sheet, bending the metal sheet along said grooves toform corresponding metal flanges, and folding the' metaivcorners to provide inturned rib formations extending inwardly between the adjacent of the flange vsections of the base sheet.

4. 'rne 'method making a hanged metal las panel formed from .a base sheet cemented to a flexible metal facing sheet. which comprises, cutf ting grooves in the base sheet to define a main secticn and a plurality of flangesections, re-

moving Y shaped segments fromv `the corners of said base sheet to denne the adjacent ends of the flange sections and substantially 'simultaneously forming a crimp in each corner sof the metal sheet, bending the metal sheet along said grooves to form corresponding metal flanges and substantially simultaneously folding the crimped corner metal inwardly to provide inlturned rib formations extending' between the adjacent ends of the flange sections of the base f 5, The method of making a flanged metal clad ,panel formed.- from a fibrous base sheet bonded to a flexible metal facing sheet` which includes.

sheet. cutting V shaped groov'es in the base sheet extending from the vortex of the corner notch and thence vgenerally parallelV to the adjacent side edges of the base sheet to define a main section 3.5 'and a pair of flange sections. the adjacent ends of uthe fibrous flange sections being cut on abevel `whereby said V-shapedl corner 4notch presents bevel faces with the corner section of the metal facing sheet exposed, bending the metal su sheet'along said grooves to form corresponding metal flanges facing the exterior of the flange sections of the base sheet, and substantially simultaneously folding themetal corneresection vvinwardly to provide a plural-ply inturned rib formation extending between the adjacent beveled ends of the flange sections of the b ase sheet, the plies of said rib-.formation being compacted together in substantiallyface tovface contact by lpressure exerted against the outer' faces ofthe outerplies by 'the adjacent beveled endsof the .flange sections of the base sheet 'as said ilange sections are bent finto final position.-

The'following references are of record in the nle of this 'vatentr UNITED STATES PATENTS Name Date 9,949 Tewksbury Aug. 10, 1853 163,088 Martyn May 11, 1875 325,374 Wright -..,s-- Sept. 1, 1885 972,113 Katzinger Oct. 4, 1910 Fairchild Dec. 28, 1915 1,711,471l Curran e Apr. 30, 1929 2,034,489 Scherer Mar. 17, 1936 2,134,051 Kirby Oct. 2 5, 1938' 2,149,882 Clements Mar. '7, 1939 

